When our oldest hit High School we camped and ATV'd a lot but I knew the days were numbered. By the time they were both in high school we sold the ATVs and bought a boat. Camping changed to us following both boys Marching Band in the fall and then Drum Corps in the summer. One is now out of College and other in college, we still camp a couple times a year and they both enjoy the break from everything. But now my wife and I take trips just the two of us, and we still follow the Drum Corps. It may not always be camping by a stream but we get out and enjoy our RV still. This past Thanksgiving we asked the boys if they wanted to camp, both of them were eager to go. :)
My recommendation is don't force it as they get older, go with the flow. Invite their friends along and make sure they get something out of it too. They will come back.
